Rupturable blister pill package with safety backing

ABSTRACT

A rupturable press-through blister type medicament or pill package is &#39;&#39;&#39;&#39;childproofed&#39;&#39;&#39;&#39; by securing to the blister sheet a laminated backing sheet having at least one strong flexible polyester layer so that the pill cannot be forced through the package unless the backing sheet is first peeled away. The blister sheet and backing sheet are left unsealed in a predetermined area to provide easier access to the package contents.

United States Patent [191 Compere Nov. 25, 1975 RUPTURABLE BLISTER PILLPACKAGE WITH SAFETY BACKING [76] lnventor: Newton L. Compere, 905Sherwood Drive, Lake Bluff, 111. 60044 [22] Filed: July 9, 1973 [21]Appl. No.: 377,326

Related U.S. Application Data [63] Continuation-impart of Ser. No.296,192, Oct. 10,

A 1972, Pat. No. 3,809,221.

[52] U.S. Cl. 206/532; 206/469; 206/484; 206/820 [51] Int. Cl. B65D73/00; B65D 83/04 [58] Field of Search 206/461, 498, 484, 820, 206/42,532, 469

[56] References Cited UNITED STATES PATENTS 2,897,962 8/1959 Zackheim206/498 3,131,069 4/1964 Goller et al.... 206/461 3,152,694 10/1964Nashed et al. 206/484 3,186,628 6/1965 Rohde 206/498 3,207,299 9/1965Sparks 206/42 3,266,625 8/1966 Hardman 206/498 3,630,346 12/1971Burnside 206/461 3,750,907 8/1973 Steele 206/484 3,809,220 5/1974Arcudi.. 206/498 3,811,564 5/1974 Braber 206/498 PrimaryExaminer-William 1. Price Assistant ExaminerAllan N. Shoap Attorney,Agent, or Firm-Mason, Kolehmainen,

' Rathburn & Wyss [57] ABSTRACT A rupturable press-through blister typemedicament or pill package is childproofed" by securing to the blistersheet a laminated backing sheet having at least one strong flexiblepolyester layer so that the pill cannot be forced through the packageunless the backing sheet is first peeled away. The blister sheet andbacking sheet are left unsealed in a predetermined area to provideeasier access to the package contents.

3 Claims, 6 Drawing Figures U.S. Patent Nov. 25, 1975 RUPTURABLE BLISTERPILL PACKAGE WITH SAFETY BACKING CROSS REFERENCE TO RELATED APPLICATIONThis application is a continuation-in-part of my copending applicationSer. No. 296,192 entitled Rupturable Blister Pill Package with SafetyBacking, filed Oct. 10, 1972.

BACKGROUND OF THE INVENTION The present invention relates to a safetyblister-type package for enclosing medication or pills. As disclosed inmy co-pending application Ser. No. 296,]92, now U.S. Pat. No. 3,809,221,one of the problems facing todays parents is in keeping medication orpills beyond the reach of their children. Children do not have theability to recognize the risk involved in consuming unprescribedmedication. Because of this fact, there is an urgent need for a packagefrom which pills are readily accessible to the adult, but not accessibleto the child.

Press-through packs or blister packs are commonly used today to packageunits of medication or pills for oral ingestion. The press-throughpackage is made up of a first sheet, typically a clear, preformedpolyvinyl chloride or polystyrene with flexible bubbles which formseparate compartments for one or more pills; and a second rupturablesheet material, like an aluminum foil or paper sheet, which has beenattached to the first sheet. The metal foil is attached by heat-sealing,solvent welding, gluing, or otherwise adhering the foil sheet to theblister sheet. The tablet is removed from the blister compartments bypressing on the flexible blister which in turn forces the tablet againstthe foil, rupturing the foil, and ejecting the tablet.

It is sometimes desirable in making such a pressthrough package toinclude between the first and second sheets a rigid tray in which thereare holes which coincide with the blisters in said first sheet. Therigid tray is used to protect the pills from contamination andmechanical damage and may contain printed instructions as to the type ofpill or the time a particular dosage is to be taken and with anindication of the dosage that has already been taken.

The recent trend in the packaging of medication has been to providepackages which will be safe, even if found by children. Mostdevelopments in the childproofing line have been directed to theimprovement in pill bottles. In this regard, safety caps have beendevised which require a certain series of pushes and turns in order toopen the bottle. However, there has been little development in the areaof childproofed presstype blister packages with which this invention isconcerned.

PRIOR ART Prior art packages which have used more than one backing layeron a press-through blister-type package have not used a layer of backingmaterial which cannot be ruptured. The prior art backing layers whichhave been used to cover the rupturable layer, have been made from paperor foil and may have been scored or weakened so that all backing layerscan be ruptured to press a pill through the package. These additionalprior art backing layers have been used for the purposes of providingprinted information on the back of the pill package and for additionalsealing engagement to protect the pills from the environment. Forexample, see

2 the following U.S. Pat. Nos.: Nagy, 3,503,493; Osborn, 3,621,992;Sorensen, 2,317,860; and Heller, 3,387,699. In each of these patents themultiple backing layers used on the blister or press-through type pillpackage can be easily ruptured or peeled away and are not strong enoughto provide childproofing.

One attempt at childproofing, a blister-type pill package, can be seenin the Helstrom U.S. Pat. No. 3,472,368. In this patent, there is nosecond backing member which is peeled away to expose the rupturablelayer as will be disclosed in describing the present invention. Thispackage is supposedly childproofedsimply by providing a rupturable sheetwhich is very difficultly ruptured. The Helstrom patent, therefore,relies on the child's weakness as the necessary element to prevent himfrom opening the package.

FIELD OF THE INVENTION The present invention was developed with the ideaof providing a pill package which requires knowledge of the packageopening procedure rather than a minimum amount of strength for openingsaid package. The person who is likely to be taking pills is notgenerally in a very strong physical condition. Quite often, the strengthof a child is greater than the strength of the person who is ill andmost likelyto be taking pills. Because of this fact, this invention wasdeveloped to provide a pill package which can be opened by theinstructed adult who may have no more strength than the average child.The child who is uninstructed on the opening of the herein disclosedpackage will not be able to reach the package contents. The presentinvention, therefore, relies on the superior knowledge of the adultrather than his superior strength in order to make a package which iseasily opened by the adult but cannot be opened by the child.

A primary object of the present invention is to provide a childproofpillpackage which can be easily opened by one who has been giveninstructions on how to do so, but cannot be opened by the uninstructedchild.

Another object of the present invention is to provide a pill packagewhich, when opened, makes only one dosage of pills accessible to theuser, which dosage, of course, is less than a lethal dosage.

Another object of the present invention is to provide a pill package inwhich any desired number of pills can be made accessible upon opening.

Another object of the present invention is to provide a pill ormedication dispensing package in which each pill or dosage of medicationis almost entirely visible to the user.

Another object of the present invention is to provide a pill package inwhich one pill or one dosage of pills can be removed from the packagewhile the remaining pills can be maintained in an air-tight enclosure.

Another object of the present invention is to provide a pill package inwhich the use of cumbersome bottles is not required.

Another object of the present invention is to provide a pill package inwhich each individual pill can be separately packaged so that thedesired dosage can be carried by the user without the necessity ofcarrying excess pills.

Another object of the present invention is to provide a pill packagewhich requires additional package opening to remove each additionalpill.

Another object of the present invention is to provide a safety pillpackage which the child cannot open without the aid of tools.

Yet another object of the present invention is to provide a pill packagein which opening of the package makes accessible a less than dangerousnumber of units of medication. The number of units exposed upon eachopening of the package can be varied depending upon the toxicity of thepackaged medication.

The present invention is concerned with a safety press-type blisterpackage which is similar to the common blister package, but which has astrong backing sheet which encloses each blister. The strong flexiblebacking sheet is secured to the back of the blister sheet in such amanner that when secured, the backing sheet is not pushed away from theblister sheet when pressure is put on the blister-side of the pillpackage in an attempt to push the pill through the package. For the userto be able to remove a pill from the package, the strong backing sheetmust first be peeled away. So long as the required adherence isobtained, the strong backing sheet can be secured to the blister sheetby heat sealing, solvent welding, gluing or otherwise adhering the twosheets together. A preferred method is by heat-sealing.

There are hundreds of heat-seal coating formulations which can be usedto provide heat-scalability between the layers of the package laminateof the present invention. These heat-seal formulations are commonly usedin making foil/paper and resin sheet/resin sheet laminates for soapwraps, carton overwraps, cereal liners, cookie wraps, and other uses.The heat-seal formulations are typically a water dispersion of a vinylresin or a vinyl resin containing wax for providing lower heatsealingtemperatures. The vinyl resin can be ion-linked and acid-modifiedethylene interpolymers known as ionomer resins. Wax and other modifiersfurther extend the range of performance properties.

The preferred heat-seal formulations are water dispersions of ethyleneinterpolymers f for example ethylene/vinyl acetate interpolymers. Thevinyl resin formulations combine broad adhesion properties with moderatehot tack. Modifiers such as pigments, waxes or other resins can be used.

It is preferred to apply the heat-seal coatings in an amount of about 2%to 4 lbs. per ream. The coatings can be applied by common methods, forexample, curtain coating or roller coatings as known in the art.

The blister sheet is made in a known manner and is made from commonblister sheet material such as polyvinyl chloride, and copolymers andterpolymers of vinyl chloride, for example the terpolymer of polyvinylchloride/polyethlene/polypropylene.

The backing sheet must have a layer or sheet of a strong flexiblepolymeric material of sufficient strength that a pill cannot behand-forced through the polymeric material. A sheet of polyestermaterial has been found to have sufficient strength to prevent a pillfrom being forced therethrough. A preferred polyester material ispolyethylene terephthalate.

A foil sheet can also be used as part of the backing sheet ifa barrierresistance coating is needed to prevent moisture from penetrating intothe blister. A metal foil, such as aluminum, having a thickness as smallas 0.001 inch is sufficient.

A sheet of paper for the purpose of printing may also form part of thebacking sheet. Bleached kraft having a basis weight of 25 pounds ispreferred. Dates, num- 4 bers, or a description of the package contentscan be printed on the paper for consumer information.

The various layers comprising the backing sheet can be laminated to forma single laminated sheet prior to applying the backing sheet to theblister sheet, or the backing layers can be secured together at the sametime they are adhered to the blister sheet. The preferred method oflaminating is by using heat-seal coatings, as previously described. Itis usually desirable to provide a paper sheet as the sheet farthest fromthe blister sheet so that printing is easily read from the bottom ornon-blister side of the package. However, if it is not necessary toprevent moisture penetration into the blister, the printed paper can bepositioned next to the transparent blister sheet and read through theblister sheet from the top of the package.

The strong polymeric sheet, foil sheet, and paper can be applied to theblister sheet in any order except that the paper sheet cannot bepositioned next to the blister sheet if it is necessary to preventmoisture from entering the blister. Thus, the strong polymeric sheet canbe positioned next to the blister sheet or intermediate between the foiland paper sheet, or as the sheet farthest from the blister. If the papersheet is between the foil and strong polymeric sheet, the polymericsheet would have to be transparent so that printing on the paper can beread by the consumer.

When applied as a single lamination structure, the layers of the backingsheet can be secured together by heat-sealing, solvent welding, gluing,applying sheets of adhesive materials between the layers, or otherwiseadhering the layers together. For example, a sheet of extrudedpolyethylene can be included between the sheet of strong flexiblematerial and the foil sheet and likewise between the foil and papersheet. The extruded polyethylene will adhere the three sheets togetherupon the application of pressure without the necessity of heat-sealing.It is preferred to use an extruded polyethylene sheet or film with aweight of about 10 lbs. per ream. Heat-seal coatings can be used inaddition to intermediate adhesive layers.

After securing the blister sheet to the backing sheet, the backing sheetcannot be forced to disengage the blister sheet by applying pressure onthe pill from the bister-side of the packet. However, the backing sheetcan readily be peeled from the back of the package so that the blistercontents can be removed. The seal between the blister sheet and backingsheet must be strong enough so that when pressure is applied to theblister, the flexible backing sheet remains in contact with the blistersheet. The backing must be strong enough so that with the backing sheetengaged, a pill cannot be forced through the backing sheet by applyingpressure to the pill from the blister-side of said package.

A strong polyester which has been found particularly effective as atleast one component of the backing sheet is polyethylene terephthalate.The thickness of the polyester is preferably about 50 gauge. However,any plastic with strength sufficient to prevent a pill from beinghand-forced therethrough can be used for this purpose.

A weakened severance line is provided across any edge of the package(top, bottom or either side). The weakened severance line is made in theblister sheet but usually not in any layers of the backing sheet.

The weakened severance line is provided by making a perforatedscoreline, thinner portion or the like which extends across any edge ofthe package. This weakened severance line extends through the blistersheet only so that when the package is angulated or flexed at the lineof weakening, the forces cause the blister sheet to be severed at theline of weakening. The smaller severed portion of the blister sheet isstill bonded to the backing sheet and together with said backing sheet,acts as a tab for peeling the backing sheet from the package.

The weakened severance line is perferably positioned along a shorteredge of the package so that when the backing sheet is peeled, thecontents of only one blister is exposed at a time. Taking into accountthe persistence and endurance of a child who has made up his mind toopen the package, the weakened severance lines can be made severableonly by a series of angular back-and-forth flexing at said severancelines. In this regard, only a few short perforations need be made tocreate severability for the instructed adult. Further, rather than aline of intermittant perforations, only a crushing force need be appliedto create a line of weakening so that the blister sheet will be madethinner along the line of crushing. The crushing force will cause adecrease in strength of the blister sheet so that severance will occurwith back-and-forth angular flexing at the severance line. Of course,the smaller the weakening effect along the severance line, the safer thepackage and the more difficult the package will be for the adult toopen. It is within the skill of the art to create a severance line inaccordance with the above disclosure which makes the packageprohibitively difficult for the uninstructed child to open, but is notunduly burdensome for the adult to open.

3 Given instructions on how to peel off the backing sheet, the user canthen flex or bend the edge of the package along the line of weakening sothat the blister sheet becomes severed along the weakened severanceline. By grasping this separated tab or edge of the package and tearingdownward parallel to the back-side of the package, the user can peel offthe strong flexible backing sheet and thereby expose the blistercontents.

It is desirable to provide an unsealed area between the blister sheetand backing sheet directly below the line of weakening in the blistersheet. In this manner, the severance of the blister sheet along the lineof weakening will expose an unsealed area helpful to initiate theseparation of backing sheet from blister sheet. The unsealed area shouldnot extend to the blister or to any edge of the package. If the unsealedarea extends to the blister, the package contents will be contaminatedand too easily accessible. If the unsealed area extends to the packageedge, the package contents again will be too readily accessible sincethe package can be opened without first peeling away the blister sheet.

The unsealed area can be provided in a number of ways. When the backingsheet is laminated to the blister sheet, pressure can be omitted from apredetermined area corresponding to the unsealed area. Without pressureto laminate the backing sheet to the blister sheet in the predeterminedarea, that area will not be sealed. Other methods of providing theunsealed area include omitting a heat-seal coating between the backingsheet and blister sheet in a predetermined area so that with theapplication of heat and/or pressure, the sheets are not sealed in thatarea. In the same manner, adhesive coatings and extruded polyethyleneadhesive layers can be applied between blister sheet and backing sheetso that a predetermined area is not covered and the sheetswill thereforenot be adhered in the non-covered area.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The invention togetherwith the above and other objects may be best understood from aconsideration'of the following detailed description of an illustrativeembodiment in the course of which reference is had to the accompanyingdrawings in which:

FIG. 1 is an enlarged plan view of the safety blister package of thepresent invention showing multiple pill packets in one package;

FIG. 2 is a perspective view of one of the pill packets shown in FIG. 1;

FIG. 3 is a perspective view of one of the pill packets of FIG. 1 inwhich the pill packet is partially opened;

FIG. 4 is a cross sectional view taken along line 44 of FIG. 1;

FIG. 5 is an enlarged fragmentary cross sectional view betterillustrating the various layers, adhesive, and unsealed area of the pillpackets shown in the previous figures.

Referring to the drawings and first to FIG. 1, a safety blister packageis indicated as a whole by the reference character 10. The package 10'may contain multiple sub-packages or packets 13 having one or moreblisters ll of any desired shape which conform to the shape of theparticular medicament or pill 21 contained within said blister. Thesub-packages or packets 13 can be separated from each other by severingthe package at lines of weakening or perforated score lines 12. Alongone edge of each packet 13, a line of weakening 14 in the blister sheet15 is provided for opening each packet. Directly under the line ofweakening 14 there is an unsealed area 20 in which the blister sheet 15has not been sealed as by heat and/or pressure to the sheet directlytherebelow. Thus, when the edge of the packet 13 is angulated or flexedalong line of weakening 14, the blister sheet 15 is severed along line14 to expose the unsealed area 20. The packet 13 can thereby be moreeasily opened by inserting the finger into the unsealed area 20 to aidin peeling back the backing sheet 25.

Backing sheet 25 as shown in FIGS. 2, 3 and 4 contain a foil barriersheet 16, a sheet of a strong flexible polymeric material for example apolyester such as polyethylene terephthalate 17, and a paper sheet 18which can have printing thereon to convey information to the consumersuch as the package contents. FIG. 2 shows tab 19 which is formed byangulating or flexing the edge of the package along line of weakening 14as explained above.

As previously set forth, the backing sheet 25 need not contain all threelayers of foil, strong flexible polymeric material and paper. However,the strong polymeric material is necessary for the purpose of providinga safety backing to the blister sheet 15 so that the pills 21 can not beforced out of the package without first peeling the backing sheet 25from the blister sheet 15.

The layers l6, l7 and 18 of the backing sheet 25 can be secured togetherby heat sealing, solvent welding,

gluing, applying sheets of adhesive materials between the layers, orotherwise adhering the layers together. FIG. 5 shows one embodiment ofadhering the blister, foil, strong flexible polymeric material, andpaper layers together by means of adhesive layers 32, 34, and 36. Theseadhesive layers 32, 34 and 36 can be applied in 7 liquid form or may beapplied as a sheet of material, for example, polyethylene which is madeadhesive by the application of heat and/or pressure. Adhesive layer 32between the blister sheet and first layer of backing sheet 16 should bea heat-seal coating so that blister sheet 15 may be heat sealed tobacking sheet 25.

The package as described herein complies with standards of the PoisonPrevention Packaging Act, 21 CFR 295.1, which describes the testprocedures in which the packages are given to children for a givenperiod of time to determine accessibility of the package contents.

It should be understood that the printing on the paper sheet can containany desired information such as a description of the item containedwithin the blister, and numbers or dates for sequential dosages. In thisregard, the package can be ealendarized as commonly seen in oralcontraceptive packages and in fact can be used to package oralcontraceptives. Of course, the package need not be in a rectangular formas shown in the drawings. The package can be circular having severancelines between individual pill packets which extend from the center ofthe circular package forming pie-shaped individual packets containing asmany items as desired. In this manner, any desired shape can be usedwith severance lines between individual packets placed to giveindividual packets containing as many items as desired.

While the present invention has been described with reference to amedicament or pill, it can also be used to make a child-resistantpackage for capsules, tablets, troches, suppositories, etc.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

l. A protective childproof package comprising:

a first sheet having one or more flexible blisters which formcompartments, each blister being adapted to receive a medicament; andhaving a line of weakening along one edge; and

a backing sheet closing and sealing the compartments formed by theblisters in the first sheet and being secured to the first sheet alongeach edge of said first sheet and over substantially the entire backingsheet surface area except at each blister and at an unsecured areadirectly under the line of weakensaid backing sheet comprising alaminated sheet of a foil sheet, a sheet of polyethylene terephthalate,and a sheet of paper wherein the backing sheet is secured together withintermediate sheets of polyethylene as an adhesive;

said backing sheet secured to said first sheet such that said backingsheet cannot be forced out of engagement with said first sheet whenforce is applied to said flexible blisters;

said backing sheet having at least one sheet of material therein whichhas sufficient strength so that the backing sheet can neither beruptured nor forced out of engagement with the first sheet when force isapplied to the medicament from the blister side of the package.

2. A protective childproof package as defined by claim 1 wherein thefirst sheet is secured to the backing sheet with a heat seal coating.

3. A protective childproof package comprising:

a first sheet having one or more flexible blisters which formcompartments, each blister being adapted to receive medicament; andhaving a line of weakening along one edge; and

a backing sheet closing and sealing the compartments formed by theblisters in the first sheet and being secured to the first sheet alongeach edge of said first sheet and over substantially the entire backingsheet surface area except at each blister and at an unsecured areadirectly under the line of weakensaid backing sheet comprising a foilsheet, a sheet of polyethylene terephthalate, and a sheet of paperwherein the backing sheet is secured together with intermediate layersof an adhesive;

said backing sheet secured to said first sheet such that said backingsheet cannot be forced out of engagement with said first sheet whenforce is applied to said flexible blisters;

said backing sheet having at least one sheet of material therein whichhas sufficient strength so that the backing sheet can neither beruptured nor forced out of engagement with the first sheet when force isapplied to the medicament from the blister side of the package.

1. A protective childproof package comprising: a first sheet having oneor more flexible blisters which form compartments, each blister beingadapted to receive a medicament; and having a line of weakening alongone edge; and a backing sheet closing and sealing the compartmentsformed by the blisters in the first sheet and bEing secured to the firstsheet along each edge of said first sheet and over substantially theentire backing sheet surface area except at each blister and at anunsecured area directly under the line of weakening; said backing sheetcomprising a laminated sheet of a foil sheet, a sheet of polyethyleneterephthalate, and a sheet of paper wherein the backing sheet is securedtogether with intermediate sheets of polyethylene as an adhesive; saidbacking sheet secured to said first sheet such that said backing sheetcannot be forced out of engagement with said first sheet when force isapplied to said flexible blisters; said backing sheet having at leastone sheet of material therein which has sufficient strength so that thebacking sheet can neither be ruptured nor forced out of engagement withthe first sheet when force is applied to the medicament from the blisterside of the package.
 2. A protective childproof package as defined byclaim 1 wherein the first sheet is secured to the backing sheet with aheat seal coating.
 3. A PROTECTIVE CHILDPROOF PACKAGE COMPRISING: AFIRST SHEET HAVING ONE OR MORE FLEXIBLE BLISTERS WHICH FORMCOMPRATMENTS, EACH BLISTER BEING ADAPTED TO RECEIVE MEDICAMENT; ANDHAVING A LINE OF WEAKENING ALONG ONE EDGE; AND A BACKING SHEET CLOSINGAHD SEALING THE COMPARTMENTS FORMED BY THE BLISTERS IN THE FIRST SHEETSURFACE AREA TO THE FIRST SHEET ALONG EACH EDGE OF SAID FIRST SHEET AREAOVER SUBSTANTIALLY THE ENTIRE BACKING SHEET SURFACE AREA EXCEPT AT EACHBLIXTER AND AT AN UNSECURED AREA DIRECTLY UNDER THE LINE OF WEAKENING;SAID BACKING SHEET COMPRISING A FOIL SHEET, A SHEET OF POLYETHYLENETEREPHTHALATE, AND A SHEET OF PAPER WHEREIN THE BACKING SHEET IS SECUREDTOGETHER WITH INTERMEDIATE LAYERS OF AN ADHESIVE; SAID BACKING SHEETSECURED TO SAID FIRST SHEET SUCH THAT SAID BACKING SHEET CANOT BE FORCEDOUT OF ENGAGEMENT WITH SAID FIRST SHEET WHEN FORCE IS APPLIED TO SAIDFLEXIBLE BLISTERS; SAID BACKING SHEET HAVING AT LEAST ONE SHEET OFMATERIAL THEREIN WHICH HAS SUFFICIENT STRENGTH SO THAT THE BACKING SHEETCAN NEITHER BE RUPTURED NOR FORCED OUT OF ENGAGEMENT WITH THE FIRSTSHEET WHEN FORCE IS APPLIED TO THE MEDICAMENT FROM THE BLISTER SIDE OFTHE PACKAGE.